1. Field of the Invention
The present invention relates to members for a rocket nozzle, and in particular to improved members and a fabrication method thereof for the rocket nozzle, capable of burning a propellant in a rocket propelling engine and jetting a gas of high temperature and pressure, thereby obtaining a thrust.
2. Description of the Conventional Art
Generally, as shown in FIG. 1, conventional members for a nozzle used for a rocket nozzle are formed of a heat-resistant element 5, a single-layered adhesive 6, and a composites structural body 1. To adhere the heat-resistant element 5 to the composites structural body 1, the single-layered adhesive 6 is stacked on the heat-resistant element 5, the composites structural body 1 is stacked on an outer surface of the single-layered adhesive 6 by a wet filament winding process, and the single-layered adhesive 6 and the composites structural body 1 are simultaneously formed by an oven-hardening, whereby such members can be obtained. However, in the conventional method, since there is a wide difference of a coefficient of thermal expansion between the heat-resistant element 5 and the composites structural body 1, the single layered adhesive 6 has an extreme residual stress. Therefore, the nozzle fabricated by simultaneously curing the single layered adhesive 6 and the composites structural body 1 in the oven may run a risk of separation of the heat-resistant element 5 and the composites structural body 1 caused by a loosening of the adhesive due to the residual stress on the single layered adhesive 6 when the inside of the heat-resistant element 5 of a nozzle extension part is exposed to a gas of high temperature, when a propellant is burned. A phenol resin is used as a base member, and a carbon fiber or a glass fiber is used to reinforce as members for the heat-resistant element 5 of the nozzle extension part. However, due to its specific properties, the phenol resin may produce pores and minute cracks inside the nozzle extension part after fabrication. And, as described above, a non-adhesion might exist between the heat-resistant element 5 of the nozzle extension part and the composites structural body 1 caused by the residual stress on the single layered adhesive 6 caused by the difference of the coefficient of thermal expansion between the heat-resistant element 5 and the composites structural body 1. If the pores, the minute cracks, or the non-adhesion exists therein, a high temperature gas will penetrate therein to via a defective route inside the heat-resistant element 5, thereby breaking the nozzle extension part.